His father, Yurii Reznikov was a professor, Master of Sports in Acrobatics, Provost of the Lviv State Institute of Physical Culture.

In 2011, Magisters was subject of a friendly takeover by Egorov, Puginsky, Afanasiev and Partners, an international group with offices in London, Moscow, Saint Petersburg, Kyiv, Minsk and Washington, D.C. Until 3 July 2014, Reznikov headed the Department for Disputes and served as General Counsel of Egorov, Puginsky, Afanasiev and Partners.

During his law practice, Reznikov defended then-presidential candidate Viktor Yushchenko before the Supreme Court of Ukraine, and the third round of the 2004 Ukrainian presidential election was annulled.

Reznikov represented B. Fuksman and O. Rodnyanskiy in their case against the "Studio 1 + 1" in the company of Central European Media Enterprises, pertaining to their share of the ownership.

Reznikov also represented several other people, including Savik Shuster, Vladimir Gusinsky, OJSC "ArcelorMittal Kryvyi Rih" company "Quasar" Sadogan Petroleum, DCH, FC Metalist Kharkiv (on charges of violating the principles of fair play), IA "IMC" Corporation " Interpipe ".

On 20 June 2014, Reznikov's advocacy license (originally issued on 10 March 1994) was suspended, due to his appointment as the Secretary of the Kyiv City Council.

[5] Reznikov has served in multiple positions, including as head of Ukraine's National delegation in Congress of Local and Regional Authorities of the Council of Europe from 2015 to 2016.

On 18 September 2019, President Volodymyr Zelensky authorised Reznikov to represent Ukraine in the working political subgroup at the Trilateral Contact Group on a Donbas settlement.

[8] On 5 May 2020 President Volodymyr Zelensky authorised Reznikov to First Deputy Head of the Ukrainian delegation at the Trilateral Contact Group.

[11] In December 2021 Reznikov stated that Germany had vetoed Ukraine's purchase of anti-drone rifles and anti-sniper systems via the NATO Support and Procurement Agency.

[14] In February 2023, the head of the Servant of the People parliamentary bloc, Davyd Arakhamia, stated that Reznikov would be replaced by Kyrylo Budanov as defence minister.

"[20] For the first time, information about Reznikov's resignation appeared after several high-ranking officials, including deputy defense ministers, were fired in Ukraine in early 2023 due to corruption scandals.

Over the next few months, it became known about a number of scandals involving the purchase of products (well known as "Eggs for 17 hryvnias") and ammunition for the military by the Ministry of Defense of Ukraine at inflated prices, and Reznikov's resignation was again talked about.

According to a source of The New York Times in the Office of the President of Ukraine, the reshuffle in the leadership of the Ukrainian department occurred for three reasons: the Ukrainian authorities believe that a new military leadership is needed due to the protracted war, Reznikov is criticized by civil society and the media against the background of corruption scandals, in addition, he himself expressed a desire to resign.